Portable water sources have proved invaluable in a wide array of situations. For example, many sports teams have water containers that they bring to practice facilities and training sites. Also, campers, hikers and backpackers have used portable liquid containers for excursions in remote areas. However, in most situations the container is typically placed in an open area, such as a field or on a travel pack. In this manner, the container is exposed to environmental conditions, especially the sun. Exposure to the sun can heat the liquid in the container; thus, eliminating the refreshing sensation provided by a cool liquid. Also, in many instances, a person can be out in the field for long periods of time and away from a source of ice for cool beverages. In some situations, ingesting a warm or hot liquid will not always quench the thirst sensation.
One particular situation where the need for a cooling device for liquid in a portable container is ever present is in the military. Soldiers must be prepared for multiple environments and climates at all times. In many tropical or desert environment, the average temperature may reach 100 degrees Fahrenheit or higher. In these situations, hydration is essential. Also, soldiers may use their water supply to clean wounds, wash their hands and face, and control their body temperature to combat exhaustion and fatigue.
Typically, soldiers will carry portable liquid containers designed for individuals. The most common portable container is the canteen. A normal canteen usually is handheld and lightweight. Canteens can be manufactured out of a hard plastic because they are light weight and prevent breaking if dropped. Due to their nature as individual use items, canteens can only hold a small amount of water and must be refilled periodically. Also, if a soldier is carrying his canteen in a desert or tropical climate and the sun has warmed the contents of his or her canteen, he or she may empty the remaining liquid because its temperature renders it unpalatable. A soldier likely will not want to carry a warmed liquid, which he or she knows will not provide a refreshing sensation when ingested.
A newer apparatus used by soldiers is the hydration system known as a CamelBak®. The hydration system is an elongated pouch which houses an amount of liquid. Attached to the pouch is a tube with a softbite valve. When a drink of water is needed, the soldier can bite down on the softbite valve and release liquid into his or her mouth. The hydration system can carry significantly more liquid then a canteen. Also, the hydration system is easier to carry, because it is worn like a backpack with a pair of shoulder straps. However, like the canteen, the hydration system is exposed to the environment and has no method or device for keeping its content cool.
Cooling device for beverage containers have been contemplated in the prior art. In U.S. Pat. No. 5,845,501 to Stonehouse et al., a shell that house liquid refrigerant is adapted to fit around the outside of a beverage container. The Stonehouse '501 device presents a significant disadvantage in that the cooling action must be transmitted through the surface of the can. The disclosure of Stonehouse '501 does not suggest that the chilling device actually contact the liquid, which would provide an instantaneous cooling effect.
A portable beverage chiller is disclosed in U.S. Pat. No. 4,460,101 to Johnson. The device in Johnson '101 is adapted to receive and enclose a beverage container. When the container is inserted into the device, it is encapsulated and cooled by a refrigerant. The Johnson patent does not suggest that the device contact the liquid itself. Nor does the patent teach that the apparatus may be attached to an opened container.
Hence, their presents a need for an apparatus that can cool a liquid in a portable container.